This invention relates to the preparation of a frozen food product for later use, and is based on an improvement over the concepts disclosed in one of the present inventors' U.S. Pat. No. 3,415,664 issued Dec. 10, 1968, the contents of which are incorporated herein by reference.
In said U.S. Pat. No. 3,415,664, there is disclosed the concept of cooking food pieces (such as meat, potatoes, carrots, peas or the like) in the presence of water. Substantially all of the free water present with the food pieces is then removed, leaving voids in the food mass. Then, the precooked food is collected into a water impervious container such as an aluminum pan or plastic bag. Subsequently, there is added to the food a mass of dry uncooked additives such as a dry powder adjuvant mix of materials which, when later reconstituted by the addition of free water, will provide flavoring, sauce, gravy or the like. Such a dry powder adjuvant may contain tomatoes, starch, onions, salt, hydrolysed vegetable protein, monosodium glutamate, spices and seasonings, etc. The container is then sealed and the food therein is then frozen while the aforesaid voids remain.
When the food is to be eaten, the container is unsealed and a desired amount of free water added to the food-adjuvant mixture and the entire mass heated. The added free water fills the voids and, as the water becomes hot throughout the mass, it dramatically shortens the time necessary to re-heat the mass to eating temperature. The free water also combines with the adjuvant to form the desired sauce, gravy or the like, as would be desired, for example, in beef stew.
The above concept is subject to the disadvantage that in thawing and reconstituting the frozen food-adjuvant mixture (as by the addition of free water and heating), the entire contents of the container must be utilized in order to obtain a final food product which contains all of the ingredients in their proper proportions in accordance with the original recipe. If only a portion of the container contents is removed and treated with free water and heated, the proportions will not normally be the same as in the recipe. This has been found to be due to an uneven distribution of adjuvant. Thus, the prior concepts are generally limited to the preparation of frozen food packages for subsequent individual serving.
It is a task of the present invention to substantially eliminate the aforementioned disadvantage so that the mass of precooked food and adjuvant can be packaged in bulk in frozen form in an economical large container in such a manner that any desired amount thereof can be removed from the container and reconstituted by free water and heat, as designated for example on an accompanying chart, while maintaining the original proportions of ingredients. Each of a plurality of batches of material so removed from the same container and reconstituted will have substantially the same proportions as every other batch and will closely conform to the original recipe.
In accordance with the various aspects of the invention, after any free water has been removed from the precooked food, leaving voids in the food mass, the food mass is agitated and the surfaces of the food pieces are treated so as to be partially frozen to thereby: (a) hold the basic shape of each piece without major deformation during agitation, and (b) leave a small amount of unfrozen moisture on the surface of each piece. Dry powdered uncooked adjuvant is then added to the food mass and, during further agitation, comes in contact with the partially frozen surface of each piece and is caused to adhere thereto by the attraction of the remaining moisture, causing a uniform coating of adjuvant to be applied to the food pieces. The resulting product is then fully frozen for deep freeze storage in a large container. Due to the uniform distribution of adjuvant throughout the food mass, subsequent reconstituting of any part thereof, or all of it at once, by the addition of suitable amounts of water and the application of heat, will result in edible dishes which have the same basic proportions of ingredients.
The food mass and the subsequently added adjuvant may be agitated by tumbling in a drum into which is introduced expanding CO.sub.2 gas to provide the freezing function. The gas may be used to assist the introduction of adjuvant into the drum from an adjuvant storage hopper having a distributor at its lower end.